Present back packs, both framed and frameless, are subject to physical shifting during movement of the wearer, particularly during extremes of movement such as occurs in mountain climbing operations, which require a considerable range of movement of the torso and the arms of the climber. In such situations, movement of the back pack and the attendant shifting of the pack load is highly undesirable, since it interferes with the climber's balances as well as restricting the range of arm movement. The present invention has been developed in order to overcome these general disadvantages of the prior art.
The principle object of the present invention is to reduce to and fro movement of the pack or carrying device relative to the wearer's body in order to stabilize the center of gravity of the aggregate mass of the pack-wearer and his load.
A further object is to permit the wearer to move his body, and in particular to bend at the waist in any direction and to extend his arms above his head without restraint, strain, or discomfort resulting from force exerted on the straps.
Further objects of the present invention are to provide means for manual adjustment of the length and tightness of the straps, for automatic adjustment of the relative tension betwen the various points at which the straps are anchored to the pack or carrying device as such tension changes due to body movements, to secure the pack or carrying device to the wearer's body so that it can not slip or be pulled therefrom, and reasonably convenient means to don and doff the pack or carrying device.
Further objects and advantages of the invention appear as the specification proceeds.